<?php
// +----------------------------------------------------------------------
// | ThinkPHP [ WE CAN DO IT JUST THINK IT ]
// +----------------------------------------------------------------------
// | Copyright (c) 2006-2012 http://thinkphp.cn All rights reserved.
// +----------------------------------------------------------------------
// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
// +----------------------------------------------------------------------
// | Author: liu21st <liu21st@gmail.com>
// +----------------------------------------------------------------------
defined('THINK_PATH') or exit();

/**
 * Mysql数据库驱动类
 * 
 * @category Think
 * @package Think
 * @subpackage Driver.Db
 * @author liu21st <liu21st@gmail.com>
 */
class DbMysql extends Db
{

    /**
     * 架构函数 读取数据库配置信息
     * 
     * @access public
     * @param array $config
     *            数据库配置数组
     */
    public function __construct($config = '')
    {
        if (! extension_loaded('mysql')) {
            throw_exception(L('_NOT_SUPPERT_') . ':mysql');
        }
        if (! empty($config)) {
            $this->config = $config;
            if (empty($this->config['params'])) {
                $this->config['params'] = '';
            }
        }
    }

    /**
     * 连接数据库方法
     * 
     * @access public
     * @throws ThinkExecption
     */
    public function connect($config = '', $linkNum = 0, $force = false)
    {
        if (! isset($this->linkID[$linkNum])) {
            if (empty($config))
                $config = $this->config;
                // 处理不带端口号的socket连接情况
            $host = $config['hostname'] . ($config['hostport'] ? ":{$config['hostport']}" : '');
            // 是否长连接
            $pconnect = ! empty($config['params']['persist']) ? $config['params']['persist'] : $this->pconnect;
            if ($pconnect) {
                $this->linkID[$linkNum] = mysql_pconnect($host, $config['username'], $config['password'], 131072);
            } else {
                $this->linkID[$linkNum] = mysql_connect($host, $config['username'], $config['password'], true, 131072);
            }
            if (! $this->linkID[$linkNum] || (! empty($config['database']) && ! mysql_select_db($config['database'], $this->linkID[$linkNum]))) {
                throw_exception(mysql_error());
            }
            $dbVersion = mysql_get_server_info($this->linkID[$linkNum]);
            // 使用UTF8存取数据库
            mysql_query("SET NAMES '" . C('DB_CHARSET') . "'", $this->linkID[$linkNum]);
            // 设置 sql_model
            if ($dbVersion > '5.0.1') {
                mysql_query("SET sql_mode=''", $this->linkID[$linkNum]);
            }
            // 标记连接成功
            $this->connected = true;
            // 注销数据库连接配置信息
            if (1 != C('DB_DEPLOY_TYPE'))
                unset($this->config);
        }
        return $this->linkID[$linkNum];
    }

    /**
     * 释放查询结果
     * 
     * @access public
     */
    public function free()
    {
        mysql_free_result($this->queryID);
        $this->queryID = null;
    }

    /**
     * 执行查询 返回数据集
     * 
     * @access public
     * @param string $str
     *            sql指令
     * @return mixed
     */
    public function query($str)
    {
        if (0 === stripos($str, 'call')) { // 存储过程查询支持
            $this->close();
            $this->connected = false;
        }
        $this->initConnect(false);
        if (! $this->_linkID)
            return false;
        $this->queryStr = $str;
        // 释放前次的查询结果
        if ($this->queryID) {
            $this->free();
        }
        N('db_query', 1);
        // 记录开始执行时间
        G('queryStartTime');
        $this->queryID = mysql_query($str, $this->_linkID);
        $this->debug();
        if (false === $this->queryID) {
            $this->error();
            return false;
        } else {
            $this->numRows = mysql_num_rows($this->queryID);
            return $this->getAll();
        }
    }

    /**
     * 执行语句
     * 
     * @access public
     * @param string $str
     *            sql指令
     * @return integer|false
     */
    public function execute($str)
    {
        $this->initConnect(true);
        if (! $this->_linkID)
            return false;
        $this->queryStr = $str;
        // 释放前次的查询结果
        if ($this->queryID) {
            $this->free();
        }
        N('db_write', 1);
        // 记录开始执行时间
        G('queryStartTime');
        $result = mysql_query($str, $this->_linkID);
        $this->debug();
        if (false === $result) {
            $this->error();
            return false;
        } else {
            $this->numRows = mysql_affected_rows($this->_linkID);
            $this->lastInsID = mysql_insert_id($this->_linkID);
            return $this->numRows;
        }
    }

    /**
     * 启动事务
     * 
     * @access public
     * @return void
     */
    public function startTrans()
    {
        $this->initConnect(true);
        if (! $this->_linkID)
            return false;
            // 数据rollback 支持
        if ($this->transTimes == 0) {
            mysql_query('START TRANSACTION', $this->_linkID);
        }
        $this->transTimes ++;
        return;
    }

    /**
     * 用于非自动提交状态下面的查询提交
     * 
     * @access public
     * @return boolen
     */
    public function commit()
    {
        if ($this->transTimes > 0) {
            $result = mysql_query('COMMIT', $this->_linkID);
            $this->transTimes = 0;
            if (! $result) {
                $this->error();
                return false;
            }
        }
        return true;
    }

    /**
     * 事务回滚
     * 
     * @access public
     * @return boolen
     */
    public function rollback()
    {
        if ($this->transTimes > 0) {
            $result = mysql_query('ROLLBACK', $this->_linkID);
            $this->transTimes = 0;
            if (! $result) {
                $this->error();
                return false;
            }
        }
        return true;
    }

    /**
     * 获得所有的查询数据
     * 
     * @access private
     * @return array
     */
    private function getAll()
    {
        // 返回数据集
        $result = array();
        if ($this->numRows > 0) {
            while ($row = mysql_fetch_assoc($this->queryID)) {
                $result[] = $row;
            }
            mysql_data_seek($this->queryID, 0);
        }
        return $result;
    }

    /**
     * 取得数据表的字段信息
     * 
     * @access public
     * @return array
     */
    public function getFields($tableName)
    {
        $result = $this->query('SHOW COLUMNS FROM ' . $this->parseKey($tableName));
        $info = array();
        if ($result) {
            foreach ($result as $key => $val) {
                $info[$val['Field']] = array(
                    'name' => $val['Field'],
                    'type' => $val['Type'],
                    'notnull' => (bool) (strtoupper($val['Null']) === 'NO'), // not null is empty, null is yes
                    'default' => $val['Default'],
                    'primary' => (strtolower($val['Key']) == 'pri'),
                    'autoinc' => (strtolower($val['Extra']) == 'auto_increment')
                );
            }
        }
        return $info;
    }

    /**
     * 取得数据库的表信息
     * 
     * @access public
     * @return array
     */
    public function getTables($dbName = '')
    {
        if (! empty($dbName)) {
            $sql = 'SHOW TABLES FROM ' . $dbName;
        } else {
            $sql = 'SHOW TABLES ';
        }
        $result = $this->query($sql);
        $info = array();
        foreach ($result as $key => $val) {
            $info[$key] = current($val);
        }
        return $info;
    }

    /**
     * 替换记录
     * 
     * @access public
     * @param mixed $data
     *            数据
     * @param array $options
     *            参数表达式
     * @return false | integer
     */
    public function replace($data, $options = array())
    {
        foreach ($data as $key => $val) {
            $value = $this->parseValue($val);
            if (is_scalar($value)) { // 过滤非标量数据
                $values[] = $value;
                $fields[] = $this->parseKey($key);
            }
        }
        $sql = 'REPLACE INTO ' . $this->parseTable($options['table']) . ' (' . implode(',', $fields) . ') VALUES (' . implode(',', $values) . ')';
        return $this->execute($sql);
    }

    /**
     * 插入记录
     * 
     * @access public
     * @param mixed $datas
     *            数据
     * @param array $options
     *            参数表达式
     * @param boolean $replace
     *            是否replace
     * @return false | integer
     */
    public function insertAll($datas, $options = array(), $replace = false, $has_id = true)
    {
        if (! is_array($datas[0]))
            return false;
        $fields = array_keys($datas[0]);
        array_walk($fields, array(
            $this,
            'parseKey'
        ));
        $values = array();
        foreach ($datas as $data) {
            $value = array();
            foreach ($data as $key => $val) {
                $val = $this->parseValue($val);
                if (is_scalar($val)) { // 过滤非标量数据
                    $value[] = $val;
                }
            }
            $values[] = '(' . implode(',', $value) . ')';
        }
        $webid = empty($_REQUEST['webid']) ? 'def_webid' : $_REQUEST['webid'];
        $date = date('Ymd');
        $this->lastInsStrID = C('DB_ID_PREFIX') . '_' . $webid . '_' . $date . '_' . $this->getRandOnlyId(); // 拼接Id，服务器前缀_研修子网编号_当前日期_6位随机数 add by xinglou 2014-6-20
                                                                                                 // $sql = ($replace?'REPLACE':'INSERT').' INTO '.$this->parseTable($options['table']).' ('.implode(',', $fields).') VALUES ('.implode(',', $values).')';
                                                                                                 // 分情况处理，表结构中存在id，生成的数据字段中有id，则用该id，没有则自动生成
        if ($has_id) {
            if (in_array('`id`', $fields)) {
                $sql = ($replace ? "REPLACE" : "INSERT") . " INTO " . $this->parseTable($options['table']) . " (" . implode(',', $fields) . ") VALUES (" . implode(',', $values) . ")"; // edit by xinglou 2014-6-20
            } else {
                $sql = ($replace ? "REPLACE" : "INSERT") . " INTO " . $this->parseTable($options['table']) . " (`id`," . implode(',', $fields) . ") VALUES ('" . $this->lastInsStrID . "'," . implode(',', $values) . ")"; // edit by xinglou 2014-6-20
            }
        } else { // 表结构中不存在id，有多少字段添加多少字段
            $sql = ($replace ? "REPLACE" : "INSERT") . " INTO " . $this->parseTable($options['table']) . " (" . implode(',', $fields) . ") VALUES (" . implode(',', $values) . ")"; // edit by xinglou 2014-6-20
        }
        // $sql = ($replace?'REPLACE':'INSERT').' INTO '.$this->parseTable($options['table']).' ('.implode(',', $fields).') VALUES '.implode(',',$values);
        return $this->execute($sql);
    }

    /**
     * 关闭数据库
     * 
     * @access public
     * @return void
     */
    public function close()
    {
        if ($this->_linkID) {
            mysql_close($this->_linkID);
        }
        $this->_linkID = null;
    }

    /**
     * 数据库错误信息
     * 并显示当前的SQL语句
     * 
     * @access public
     * @return string
     */
    public function error()
    {
        $this->error = mysql_errno() . ':' . mysql_error($this->_linkID);
        if ('' != $this->queryStr) {
            $this->error .= "\n [ SQL语句 ] : " . $this->queryStr;
        }
        trace($this->error, '', 'ERR');
        return $this->error;
    }

    /**
     * SQL指令安全过滤
     * 
     * @access public
     * @param string $str
     *            SQL字符串
     * @return string
     */
    public function escapeString($str)
    {
        if ($this->_linkID) {
            return mysql_real_escape_string($str, $this->_linkID);
        } else {
            return mysql_escape_string($str);
        }
    }

    /**
     * 字段和表名处理添加`
     * 
     * @access protected
     * @param string $key            
     * @return string
     */
    protected function parseKey(&$key)
    {
        $key = trim($key);
        if (! preg_match('/[,\'\"\*\(\)`.\s]/', $key)) {
            $key = '`' . $key . '`';
        }
        return $key;
    }
}